Behavior Of Double-skin Tubular Columns Research Articles

Seismic behavior of FRP-concrete-steel double skin tubular columns with a rib-stiffened Q690 steel tube and high-strength concrete

Fiber-reinforced polymer (FRP)-concrete-steel double skin tubular columns (DSTCs) are a form of novel hybrid columns with a particular merit of lightweight due to the existence of the void core. Utilization of high-strength materials (e.g., high-strength steel (HSS) and high-strength concrete (HSC)) tubes in DSTCs amplifies the advantage of DSTCs by earning a further decrease in the dead weight. In this study, behavior of DSTCs with HSC and a rib-stiffened HSS tube (referred to as R-DSTCs in this paper) under seismic loadings was experimentally investigated. The influences of the quantity of stiffeners, the FRP tube thickness and the axial load ratio on the seismic behavior of R-DSTCs were investigated. The test results demonstrate that DSTCs with HSC and HSS tubes exhibit a good seismic behavior, and an increase in the number of ribs leads to an increase in the lateral loading capacity, a small increase in the stiffness, a significant increase in the resistance to stiffness degradation and an increase in the energy dissipation of the R-DSTCs. Additionally, the axial load ratio and the GFRP tube thickness has a small effect on seismic performance of DSTCs.

Compressive Behavior of Double-Skin Tubular Columns with High-Strength Concrete and a Filament-Wound FRP Tube

AbstractHybrid fiber-reinforced polymer (FRP)–concrete–steel double-skin tubular columns (DSTCs) consist of an outer FRP tube and an inner steel tube, with the space between them filled with concre...

Reflections on Mechanisms Affecting the Behavior of FRP-Concrete-Steel Double-Skin Tubular Columns

This paper presents the results of 20 hollow and concrete-filled double-skin tubular columns (DSTCs), which were tested as part of a comprehensive experimental program that was undertaken at The University of Adelaide on FRP-concrete steel DSTCs. The paper is aimed at providing important insights into the influence of two key parameters, namely the diameter of inner steel tube and presence/absence of a concrete-filling inside the inner steel tube, which play major roles in the column behavior through their influences on a series of interacting mechanisms that govern the complex system behavior. A detailed examination of the results yielded a number of important insights into the mechanisms that influence the compressive behavior of DSTCs.

Effect of Inner Steel Tube Cross-Sectional Shape on Compressive Behavior of Square FRP-Concrete-Steel Double-Skin Tubular Columns

Recently, a new type of composite system was proposed in the form of fibre reinforced polymer (FRP)-concrete-steel double-skin tubular columns (DSTCs). The performance of this column system, which consists of an outer tube made of FRP and an inner tube made of steel, has been experimentally investigated in a number of studies. However, apart from a single study reported on square DSTCs, all of the existing studies have been concerned with DSTCs with circular external tubes. This paper reports on part of an ongoing experimental program at the University of Adelaide that was aimed at addressing this research gap. The effect of cross-sectional shape of inner steel tube on compressive behaviour of square DSTCs was investigated through the test of 16 hollow and concrete-filled DSTCs. The result of the experimental study indicate that concrete in hollow DSTCs with circular inner steel tubes develop significantly larger ultimate axial stresses and strains than concrete in companion hollow DSTCs with square inner steel tubes. On the other hand, the results also indicate that the presence of a concrete-filling inside inner steel tubes results in a significant improvement in the behavior of DSTCs with square inner steel tubes.

Effect of Loading Pattern on Performance of FRP-HSC-Steel Double Skin Tubular Columns

This paper reports on part of an ongoing experimental program at the University of Adelaide on FRP-concrete-steel double-skin tubular columns (DSTCs). The main emphasis of the study reported in this paper was to investigate the influence of loading pattern on the axial compressive behavior of DSTCs. To this end, 12 hollow and concrete-filled DSTCs were manufactured and tested under monotonic or cyclic axial compression. All of the specimens were manufactured using high-strength concrete (HSC). The results of the experimental study indicate that that concrete in cyclically loaded hollow DSTCs exhibits slightly larger strength and strain enhancement ratios than concrete in companion monotonically loaded DSTCs. The results also indicate that concrete in filled DSTCs exhibit slightly larger strength enhancement ratios than and similar strain enhancement ratios to concrete in monotonically loaded DSTCs.